Coupling



Oct. 3, 1944; A. G. HERRx-:sHor-'F ET AL 2,359,555

ATTRNEYS EET-'5.

ETE. 2

f n INVENTORS 29 mwl.. ALEXANDER QHERRESHUFF 's 15,-'. BY WADE LAMB* Patented Oct. 3, 1944 UNITED STATES PATENT OFFICE COUPLING Application October 30, 1941, Serial No. 417,170

16 Claims.

This invention relates to couplings and refers more particularly to improvements in the assembly and fastening together of parts of mechanisms, devices, machines, and machine elements. Our invention, in its more limited aspects, relates particularly to engine crankshafts and provides an improved crankshaft assembly and fastening means for the parts thereof.

One object of our invention is to provide an improved assembly of parts held together under high stressv inconjunction with means accommodating accuracy in obtaining the desired degree of stress.

Another object is to provide improved locking means for fasteners of assemblies as aforesaid.

A further object is -to provide a coupling embodying stressed fasteners so arranged as to guard against subjecting lthe fasteners to a twisting load during assembly of the coupling.

An additional object is to provide an improved crankshaft assembly embodying a power takeofl' gear.

Further objects and advantages of our invention will .be more apparent as this specification progresses, reference being had to the accompanying drawing illustrating the principles of our invention and in which:

Fig. 1 is an elevational view of a portion of our assembled crankshaft.

Fig. 2 is a transverse sectional elevational view taken as indicated by line 2-2 of Fig. 1.

Fig. 3 is a longitudinal sectional view taken as indicated by line 3'-3 of Fig. 2.

Fig. 4 is a detail sectional view taken as indicated byline 4 4 of Fig. 2.

Fig. 5 is a side elevational view of one of the locking devices as seen in Fig. 2.

Fig. 6 is a side elevational view of the Fig. 5 locking device.

Fig. '7 is an enlarged view of a dowel portion of one of the fastener studs.

Fig. 8 is a view similar to Fig. 5 but showing a modification.

Referring to the drawing we have illustrated our invention in the form of a crankshaft assembly, this assembly comprising the crankshaft portions A and B fastened together through the medium of a power take-olf gear C. Component parts of a variety of other devices may be assembled together within keeping of the broader phases of our invention.

Each crankshaft portion A and B terminates inwardly of the assembly in an annular ange I0 extending longitudinally of .the assembly or axially of the crankshaft, and an annular flange I I extending transversely outwardly from an adjacent crankshaft bearing portion I2. The gear C has an axial opening I3 for seating on flanges I0 and a flat wall I4 at each end of the gear for frictionally engaging the inner face of an adjacent flange I I.

Each flange II is formed with a series of circumferentially spaced axially extending cylindrical openings I5 therethrough. These openings I5 are preferably even in number and they are f located uniformly around each flange I I so that each is spaced the same distance from the circumferentially adjacent opening. Each flange II is also for-med with a second series of circumferentially spaced axially extending cylindrical openings I6 therethrough, the inner end portion of each of these openings having internal serrations I1. The openings I6 are also preferably even in number equal to the number of openings I5 and they are located uniformly around eachv flange II so that an opening I6 is spaced midway between an adjacent pair of vopenings, I 5, the axes of all openings I5 and I6 of'each flange II lying at equal distances from the crankshaft axis I8. The openings I6 are relatively larger in diameter by a small amount than the openings I5.

The intermediate element C of the coupling is formed with a series of circumferentially spaced axially extending cylindrical openings I9 therethrough. These openings I9 are equal in number to the total number of openings I5 .and I6 in either flange I I and are so disposed as to axially align .with the respective openings in flanges II The openings I9are preferably equal in diameter to that of openings I5. 1n assembling the coupling parts A, B and C, each opening I5 of each flange II is axially aligned with an opening I9 and also with an opening I6 of the other flange II to form a set of aligned stud-receiving apertures. When so related the coupling then receives the tie means in the form of rods or studs D for holding the parts together.

The studs D are interchangeable, each comprising a central portion 20 of reduced diameter lying within an opening I9. Adjacent one end, each stud is formed with an enlarged pilot portion 2| which bridges a portion of gear C and ange II adjacent a face I4 thereby serving to axially align the couplingparts. Outwardly of the pilot portion 2I, each stud is terminally threaded at 22 adjacent its end 23 to receive'corresponding threads of a nut E each of which has an inner shank portion 24 and Yan outer portion 25 of enlarged diameter which is axially serrated at 26. The enlarged serrated portion 25 forms an an- .inner return-bent :spring portion 32.

' flange.

maining .studs `D until their shoulders V2'I .engagel nular shoulder 2'I with the inner portion 24 of each nut E.

Adjacent the other end 28, each stud D is formed with an enlarged portion externally serrated. at 29 to fit serrations I1, this stud end portion being likewise threaded at 39 to receive a nut E. In assemblying the studs D, the ends 23 of half of the total number o`f studs are inserted from one end of the assembly through each set of aligned openings IB, I9 and I5 and the remaining studs are similarly inserted from the opposite end of the assembly so that the ends V28 alternate circumferentially with the ends 23 at each end of the assembly. When assembled, each stud has its serrations 29 engaging Vserrations I'I Y of an opening I6, a pilot portion vZI serving to align the associated pairs of openings I5 and I9.

Locking means is Vprovided for the nuts E comprising a plurality of devices F each of which comprises a main outer body portion 3l and an The Dortion 32 is formed with apair cf .oppositelyopening cavities 32a and 32O in its .opposite sides, each cavity comprising an intermediate serrated po-rtion 33 and end flanges 34 which lare offset inwardly of body portion 3I toward portion 32.

After the studs D'have been inser-ted in place as aforesaid, the locking devices F are assembled along'with nuts `E. One manner of completing theu assembly is as follows: A nut E is threaded! on alternate bolts D at one flange I-I and -then the locking devices Fare associated with each of vice' F engaging the :serrations `26 of the associ'ated'nut and flange 34 `fitting behind lshoulder 2'I.f EachV spring portion :32Veengages the outer face of ange II biasing .the .nuts away `from the Then nuts E are threaded on `the re- .the'flanges 34 of the devices F. The nuts E and devices F .are positioned in iplace at ithe other flange II in similar fashion so that each .adjacent .pair o'f studs D is bridged adjacent .each

Yiian'gevII yby a device .F which engages the .ser-

r'ations `of the V:nuts mounted ion the respective ends .of lsuch pairof studs. The assembly .is then :ready forthe final tensioning .of .studs D as Iollows:

A `'serrated socket wrench is then engaged with the serrations 26 .of the nuitsE ywhich are mounted on 'the ends 28 of studs D. As vthe wrench G `-is lso engaged it pushes ibody `portion 33| -of the associated device lF inwardly so fas to disengageserrations 33 and 25 leaving the wrench free to rotate the engaged 4nut E 'as illustrated in VFig. 4. As thisnut is turned to obtain the "desired degree of tension in the Iconnecte-rdfst-ud D, the studis prevented from being subjected to recesses with the two nuts E vbridged .by vdevice F thereby'preventing `any rotation lo'f .these .nuts from their desired positions. By 'rst tightening )the nuts at .stud ends V28 adjacent one Vflange II. and then tightening :thenuts at stud ends 28 adjacent the other ilange `II 'it will be apparent that 'at Vall times one of the .devicesli1 is locking 'a'pair of nuts for two studs including the stud whose nut is being tightened at its Opposite end. '.Ihis arrangement insures 'against anyV rotation Cil Ill)

Vtions 2l.

of the nuts at one side of gear C while adjustments are made on the nuts at the other side. When one nut is being tightened on one stud, the nut on the opposite end of such stud serves as an abutment anchoring the stud lengthwise.

Our arrangement accommodates a ne adjustment of the nuts so as to stress all of the studs equally and to maintain the desired adjustment of the nuts without danger of loosening. By tightening only those nuts which'are at the stud ends 28 adjacent serrations 29, less torque application is required for a desired tensioning of the studs than in instances where the nut on the remote end is tightened because in the latter instance a large shearing stress would be introduced in the stud whereas with our arrangement the stud is relieved of twisting load. In order to advise the operator of the proper stud ends for carrying out the assembly, the stud ends 28 may bear any identifying indicia such as the electric pencil mark x .shown in Fig. 2, lit being understood that the .other studs which yare `unmarked in Fig. 2 are likewise marked at their opposite ends.

VBecause of .the great degree of machining ac- Curacy which Vis required in .exactly aligning the studs with openings .I.6, .I9 .and I5 so that the dowel portion y2l of each stud exactly registers with and bears in .openings I5 and 19, `we prefer to provide .a small clearance 35 for the'dowelz-por- In Fig. '7 this clearance is .exaggerated for `purpose of illustration and in practice would be in the neighborhood of around .005 tof an inch total clearance for each dowel. Torsional vibrations in the vcrank shaft .as well as iiuctuations in the load at gear AC makes yitrdesirable to insure against any relative .rotation 4between gear C and crankshaft portions A'and B.- Therefore the studs D are highly tensioned `to provide suincient friction between the abutting parts .of gear C with .crankshaft portions A and B tofinsure against any relative movement. If the assembly should lose .this friction, for any unforeseen reason, .then .thedowel por-tions 2.I will act'to maintain the parts assembled until 'the defect -is .cor-

rected.

The. locking device `F in Fig. is an alternative vform lof device The device 2F has its cavities 32C and 32d of `annular fior-m` instead of heini-annular as in Eig. 5. Eaoh-cavityhas 'two sets or regions serrated 7'at 33. The device F is otherwise as set `forth for device .and the oper. ation is identical.

We claim:

1. A coupling comprising, coaxial .shaft sections, a gear disposed between said sections for frictional engagement therewith, and Aclamping -means for urging said sections towardeach other thereby to urge said sections into frictional fen- .gagement with .said gear `thereby to normally prevent rotation of said gear relative to said/sections, said clamping means being so constructed and arranged as to accommodate, on `failure of said frictional engagement, limited rotation of said ,gear relative to said sections.

2. A ,coupling comprising, coaxial shaft sections, a vgear disposed between said sections, and -a plurality of .-tie members extending between said sections and with clearance through said gear thereby to frictionally connect `said :gear with said sections so as .toigpreventurotation of said ,.gearrelative to .saidsections such rotation being Yotherwise -accommodated by reason of isaid clearance.

3. A .coupling 4for securing together :as 1an ase.

sembly a gear in position between coaxial shaft sections, comprising. a plurality of studs each having a connection adjacent one end thereof with one of said sections adapted to hold said studs against rotation relative to said one 'section and a piloting portion for said gear and the other of said sections adjacent the other end thereof.

4. A coupling for securing together as an assembly a gear in position between coaxial shaft sections each of which has a flange extending transversely of said axis for engagement with a side face of said gear, said anges having a plurality of apertures extending therethrough with each aperture of one ange disposed in axial alignment with an aperture of the other flange, tieing means comprising a plurality of studs respectively extending through said axially aligned apertures, each of saidv studs having a serrated portion in engagement in one flange aperture, a piloting portion in engagement in the other flange aperture, van abutment adjacent the pilot portion and a tensioning nut adjacent the serrated portion.

5. A coupling for securing together as an assembly a gear in position between coaxial shaft sections, comprising, a plurality of studs each having a connection adjacent one end thereof With one of said sections adapted to hold said studs against rotation relative to said one section and a piloting portion for said gear and the other of said sections adjacent the other end thereof, certain of said studs having said nonrotating connection with one of said sections and the remainder of said studs having said nonrotating connection with the other of said sections.

6. A coup-ling for securing together as an assembly a gear in position between coaxial shaft sections, comprising,` a pair of studs, one of said studs being provided With a non-rotatable connection adjacent one end thereof with one of said sections and a piloting portion for said gear and the other of said sections adjacent the other end thereof, the other of said studs being provided With a non-rotatable connection adjacent one end thereof with said other section and a piloting portion for said gear and said one section adjacent the other end thereof.

7. A coupling for securing together as an assembly a gear in position between coaxial shaft sections each of which has a ange extending transversely of said axis for engagement with a side face of said gear, each of said flanges having a' pair of apertures extending therethrough such that each aperture of one flange is disposed in axial alignment with an aperture of the other iiange, tieing means comprising a pair of interchangeable studs respectively extending through said aligned apertures and provided with a serrated portion adjacent one end thereof and a piloting portion adjacent the other end, said studs being directed in relatively opposite directions such that the serrated portion of one ofl said studs engages the aperture of one of said flanges While the serrated portion of the other of said studs engages the aperture of the other of said flanges and such that the piloting portion of one of said studs is disposed within the aperture of one of said flanges while the piloting portion of the other of said studs is disposed within the aperture of the other of said flanges.

8. A coupling for securing together as an assembly a gear disposed between coaxial shaft sections each having a portion thereof formed with a pair of apertures so arranged that the apertures of one section-portion are respectively aligned with the apertures of the other sectionportion, comprising; a pair of studs respectively extending through the aligned apertures of said section-portions, one of said studs being yprovided with a non-rotatable connection adjacent one end thereof with the aperture of said one section-portion and a piloting portion adjacent.

the other end thereof for the aperture of said other section-portion, the other of said studs being provided with a non-rotatable connection adjacent one end thereof with the aperture of said other section-portion and a piloting portion adjacent the other end thereof for the aperture of said one section-portion, a pair of nuts bearing on said one section-portion and respectively threadedly engaging one end of said studs, a second pair of nuts bearing on said other sectionportion and respectively threadedly engaging the other end of said studs, and releasable locking means bridging each of said pairs of nuts and operating to prevent relative rotation between each of said pairs of nuts. y

9. A coupling for securing together as an assembly a geardisposed between coaxialV shaft sections each of which is provided with a flange extending transversely of said axis and each ange being provided with a pair of apertures extending therethrough such that each aperture of one flange is disposed in axial alignment with an aperture of the other flange, said gear being disposed between said flanges and -having a pair of apertures respectively aligned with' said aligned apertures of the iianges, comprising, a pair of interchangeable studs respectively eX- tending through said aligned apertures of said Y gear and sections and provided with a serrated portion adjacent one end thereof and a piloting portion adjacent the other end, said studs being directed in relatively opposite directions such that the serrated portion of v one of said studs engages the aperture of said one flange while the serrated portion of the other of said studs engages said other flange and such that the piloting portion of one of said studgs is disposed within aligned apertures of said gear and said one iiange while the piloting portion of the other 0f said studs is disposed within the other aligned apertures of said gear and said other flange, a pair of nuts bearing on `said one flange and respectively threadedly engaging one end of said studs, a second pair of nuts bearing on said other flange and respectively threadedly engaging the other end of said nuts, and releasable locking means bridging each of said pairs of nuts and operating to prevent relative rotation between each of said pairs of nuts.

10. A coupling according to claim 8; each of said nuts having a shankportion and a second portion of relatively enlarged diameter externally serrated and providing a shoulder adjacent said shank portion; each of said locking means comprising a member having an outer body portion and spring means portion engaging one of said section-portions for biasing said body portion outwardly therefrom, said body portion having a pair of oppositely opening cavities, each of said cavities having a portion internally serrated for engagement with the external serrations of one of the nuts of a pair bridged by the locking means and a second portion offset relative to said body portion for engagement with the shoulder of the last mentioned nut thereby limiting outward movement of said body portion by said spring means while accommodating inward springing movement of said body portion .to release the internal serrations of said cav-ities from :engagement with vthe 'external serrations vof said :bridged pairof nuts.

v 11. `A coupling for securing together as an assembly a pair of outer members and a third lmember intermediate said pair, each of said members having a pair of openings so arranged that each 4openingof eachV member is aligned With :an -'opening -zof the -other two members Vthereby to provide -two sets of ltie-rod-receiving apertures I-each'oi which has a component opening in each rof said members, comprising a tie-rod extending Vthrough one rof said sets of apertures having a non-rotatable `connection in the component A.opening of one of said outer members and a piloting portion bridging the component openings in saidthird member and the other of said vouter members, a second ktie-rod extending 1,through the other of said sets of apertures having aV non-rotatable connection in the component Aopening of said other vouter member and a piloting portion bridging the component openings in said third member and said .one outer member, an abut-ment on the 1Iirst said tie-rod adjacent yitssaidpi-loting portion and bearing on said other router member, a vnut threaded on the first said -tie-rod adjacent its said non-rotatable connection for tensioning 4this tie-rod, an abutment on v.the second tie-rod adjacent its -said piloting por tion-and bearing -on said one .outer member, and `anut threaded on the second tie-rod adjacent its :said non-rotatableconnection for tensioning this tie-rod.

l2. A coupling kaccordi-ng to claim 11, locking means bridging said tie-rods adjacent each of said outer members `for preventing rotation of said nuts relative Ato said abutments.

13. A coupling for a plurality of parts comprising, a pair of tie-rods adapted to be tensioned `for -tieing said parts together, a serrated shouldered nut threaded on each of said tie-rods, and locking means comprising a body bridging said nuts, said 'body having serrated portions respectively engaging the serrations of said nuts,

said body also `having portions offset therefrom axially of saidte rods for engaging said shoulders of said nuts, and means biasing said :body

to engage said oiiset portions with the respective shoulders of said nuts, said .biasing means accommodating displacement of said body portion axially of said tie-rods for releasing said serrated portions of said lbody portion from engagement with said nuts.

tation of said third element relative to said pair of elements, .said members including means so arranged and constructed as to clamp said third element between said pair of elements upon tensioning of said members, and said members being suiiiciently tensioned whereby the frictional grip of said pair of elements upon said third element is-adequate to accommodate the torque load to be transmitted between said elements Without producing relative rotation between said elements and transverse shear in said members.

15. A coupling as claimed in claim 14, Wherein the elongated members have an abutment With one of said pair of elements, a connection with the other of said pair of elements adapted to hold said members fromrrotation, and a tensioning nut threadedly secured thereto and abutting said element having said connection.

16. A nut locking member for coupling tierods comprising, a body portion having a, pair of spaced apart internally serrated recesses, an end flange projecting within each recess and outivardly offset from one iace of said body portion,

and a bent portion resiliently connected to said body portion and overlying .the vface thereof from which said end flanges are offset.

ALEXANDER G. HERRESI-IOFF'. WADE LAMB. 

